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US 395 - Deer Park Intersection Improvement Study

Update – June 7, 2018
There have been at least 35 intersection-related crashes (27 entering-at-angle) at the study intersections since the study effort began in November 2015: seven at Burroughs/Dalton, five at Short/Main, seven at Cleveland/H Street, fourteen at Monroe/Crawford, and two at Dahl Road. These include a serious injury at Short/Main, a serious injury at Monroe/Crawford, and a fatality at Dahl Rd.

Study Description:
The previous study of this area (2003 Route Development Plan) resulted in a bypass proposal that has little prospect of funding and is not under consideration at this time. This study focused on developing lower-cost project alternatives (under $5,000,000) to improve operations and safety at the intersections on US 395 in the Deer Park vicinity. The Eastern Region Program Management, Traffic, Planning, and Design offices developed a team to complete the study ensuring public involvement.

Identifying the Need:
The opportunity for improvement was identified through WSDOT's screening process, which uses the Highway Safety Manual's Safety Analyst tool in the identification of sites on the state system with the potential for reducing crash severity or frequency. Here is a link to our crash analysis diagrams (pdf 3.5 mb).

Public Involvement:
Public input is crucial to the process. To date we have been in contact with the community through these opportunities:

US 395 Community Meeting (WSDOT as a guest)

Previous Constituent Response

Stakeholder & Local Agency Meetings

Project Study Public Comment Forms

Deer Park Chamber of Commerce Meetings

Deer Park City Council Meeting

Local Business Owners

Stevens & Spokane County Commissioners

Deer Park Public Open House

Northeast Washington Regional Transportation Planning Organization

Colville Open House

Study and Alternatives:
The study team evaluated several methods to deal with intersection movements. Here is a link to the 2015 Intersection Traffic Volumes (pdf 1.1 mb). These included turning movement restrictions, constructing u-turn locations (to accommodate restricted movements), traffic signals, roundabouts, splitting four-leg intersections into two three leg intersections, and grade separations. The study team evaluated crash reduction potential as well as changes in traffic patterns, effects on the environment, costs, freight movement, and need for right-of-way purchase. Here is a pdf of the "Alternatives Considered" (pdf 1.8 mb) presented at the Open House.

The original recommendations were to close all access at Burroughs/Dalton and construct single-lane roundabouts at Short/Main and Monroe/Crawford. No changes were proposed at Cleveland/H or Dahl. Here is a pdf of the "Recommended Alternative" (pdf 1.1 mb) presented at the Open House.

We selected Short/Main for a roundabout rather than Burroughs/Dalton in considering the capacity and availability of the local system to handle the change, and the opportunity to address an intersection with higher entering volume. From previous experience, we also anticipate that drivers will find Short/Main more accessible than Cleveland/H and change their habits. Thus, this alternative will address performance at three intersections, and potentially four. On the other hand, we understand that closing access is controversial. It requires drivers to change their driving patterns and it requires analysis to determine effects on the routes drivers may choose. If you are affected by the proposed closure we would like to hear from you as it will improve the analysis of the change.

Your feedback on this proposal is important
While the Open Houses have already occurred, your feedback is always welcome. Please contact the study team:

Why Roundabouts?
Studies have shown that roundabouts are safer than traditional stop sign or signal-controlled intersections. Roundabouts reduced injury crashes by 75 percent at intersections where stop signs or signals were previously used for traffic control, according to a study by the Insurance Institute for Highway Safety (IIHS). Studies by the IIHS and Federal Highway Administration have shown that roundabouts typically achieve a 37% reduction in overall collisions, a 75 percent reduction in injury collisions, and a 90 percent reduction in fatality collisions. The state of Washington has over 150 roundabouts. State, County & City agencies continue to pursue this intersection control for these reasons:

Why can't we just lower the speed limit?
Existing traffic data analysis does not support lowering the speed limits.
But it is more than that. If the speed limit were lowered to 45mph (the most common speed people suggest), this would be for at least 2.5 miles. This adds 50 seconds to travel. However, this does not address the intersection geometry or improve intersection operations: the time the driver on the side street needs to negotiate the gap in traffic is the same regardless of the speed. When considering the additional time needed to slow down to negotiate the roundabouts, the two roundabouts will, on average, add around the same 50 seconds of travel on US 395, but create more opportunities for drivers on side streets to enter because drivers need less of a gap.

Lowering the speed does not address crashes as well as a roundabout. Further, if people on the side street are expecting traffic to be approaching at the lower speed limit and they enter traffic only to find out differently, that can lead to an undesirable outcome.For further information on speed limits, here's an information page (pdf 766 kb).

What about a traffic signal?
Existing data analysis and state policy do not support installation of traffic signals at these locations.

The guidance in Section 4B.04 of the Manual on Uniform Traffic Control Devices is to consider alternatives to traffic signals, even if one or more of the signal warrants has been satisfied.

To summarize why traffic signals are not supported:

When a signal is installed other types of crashes, notably rear-end collisions, usually increase.

Signals almost always create more "overall intersection delay". As a result, many drivers switch to less desirable alternate routes to avoid the added delay. Minor movements may experience excessive delay while the signal is serving the mainline heavy flow. During off-peak hours, mainline traffic often has to stop to serve one or more minor movement entering vehicles

A single-lane roundabout lessens the number of intersection conflict points and provides statistically better crash reduction.

What about acceleration / deceleration lanes?
Incorporating acceleration / deceleration lanes for turning movements on major streets at intersections can increase intersection capacity and efficiency. These designated areas allow for turning traffic to move away from the main lanes or to join traffic with a reduction of interrupting the major street flow. With additional lanes comes additional width, potentially increasing problems for pedestrians and vehicles to cross the intersection. The cost to construct these lanes for the crash reduction provided is less favorable than the roundabout option.

What about an interchange or a grade separated crossing?
The primary reason is that our policy is that if an analysis determines that an at-grade intersection can provide adequate performance, then a grade separation or an interchange is not to be evaluated. The recommended project will provide improved intersection operations over the existing conditions.

Additionally, an interchange or a grade separated crossing is outside of current funding limits and availability. Assuming one was within funding limits, in order for it to be cost-effective for crash reduction multiple intersections would be closed or access restricted.